Cisco Cisco Explorer Set-top Software Version 2.1 사용자 가이드

Glossary

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GBAM

Global broadcast authenticated message. GBAMs provide a mechanism that allows IPPV

purchases to be secured. The combination of tokens required to purchase specific events.

HAL

Hardware adaptation library.

HDTV

high-definition television. The high-resolution subset of the DTV system.

headend

The location of the network elements that processes the signal by receiving and preparing the

source signals and making them ready for the transport network. See also network elements.

heap

A segment of memory used by a program.

horizontal resolution

The number of vertical lines (or pixels) that can be resolved from one side on an image to the

other side.

hub

Physical locations designed to serve a specific number of subscribers, usually 50 to 15,000.

May be co-located with the headend or miles away from the headend. Hubs receive,

modulate, and boost the signal prior to sending it to the network of HFC nodes for

distribution to the subscriber. Hubs usually contain QPSK modulalators/demodulators that

establish the two-way communications with the DHCTs.

inband

Interactive content sent as part of a broadcasted data stream (like MPEG-2).

Internet Protocol

The standard protocol within TCP/IP that defines the basic unit of information passed across

an Internet connection by breaking down data messages into packets, routing and

transporting the packets over network connections, then reassembling the packets at their

destination.

See Internet Protocol.